Kennedy Jr. has previously said that if Republican President-elect Donald Trump won the White House, the administration would advise water systems in the United States to remove fluoride. This is despite experts and officials saying the mineral is both safe and beneficial to people’s dental health.

With President-elect Donald Trump in the White House, the 21st century may be another story. Robert F. Kennedy Jr., whom Trump has pledged to let “go wild” on public health under his administration, is an outspoken opponent of adding fluoride to drinking water. He intends to take action.

Robert Kennedy Jr., poised for a health job in a potential Trump administration, said he would prioritize removing fluoride from drinking water. Here’s what to know.

The Centers for Disease Control call the addition of fluoride in water one of the biggest medical advances in the 20th century, noting that it led to healthier teeth.

The water you drink might be different after the next president takes office. Robert F. Kennedy Jr. is expected to have a spot in the Trump administration, and he wants public water systems to remove fluoride.